Combustion system

Abstract

A biogas combustion system that obtains a stable output and saves energy is realized. A combustion system comprises a separation portion 14 that removes carbon dioxide from a treatment target gas containing a mixture gas containing methane as a main component and containing carbon dioxide to obtain methane gas of a high purity in which at least a content of carbon dioxide has been reduced, and a combustion portion 15 that combusts the methane gas. The separation portion 14 includes a first treatment chamber 11 and a second treatment chamber 12 separated from each other by a separation membrane 13 therebetween. The separation membrane 13 selectively allows the carbon dioxide in the treatment target gas supplied to the first treatment chamber 11 to pass therethrough to the second treatment chamber 12 to obtain a first separation gas having a higher methane purity than the treatment target gas in the first treatment chamber 11 and a second separation gas containing the carbon dioxide in the treatment target gas in the second treatment chamber 12.

Description

PRIORITY CLAIMS[0001]This application is a continuation of U.S. application Ser. No. 16 / 078,620, filed 21 Aug. 2018, which is a U.S. national stage filing of PCT / JP2017 / 005881, filed 17 Feb. 2017 and claims priority to PCT / JP2016 / 057453, filed 9 Mar. 2016.TECHNICAL FIELD[0002]The present invention relates to a combustion system for obtaining energy by combusting a gas containing carbon dioxide and methane as a main component such as a biogas obtained by methane fermentation of organic matter such as biomass and organic waste.BACKGROUND ART[0003]In recent years, it has drawn attention to utilize, as a new energy source, a biogas obtained by methane fermentation of organic waste such as biomass and sewage sludge. The biogas is used as a substitute for fossil fuel, and is used for power generation, boiler, and the like.[0004]Biogas generally contains about 40% of carbon dioxide in addition to methane, although the content varies depending on the production conditions (fermentation cond...

AI Technical Summary

Benefits of technology

The system achieves stable engine output without complex control mechanisms, reduces energy consumption, and maximizes the environmental advantages of using biogas by using a facilitated transport membrane for CO2 separation, enabling the reuse of CO2 and minimizing environmental burden.

Problems solved by technology

These trace impurities affect the performance and durability of gas engines.

In a biogas engine, carbon dioxide in the biogas causes decrease in output and thermal efficiency of the gas engine.

As a result, since the facility cost of the engine is almost proportional to the output thereof, the facility cost increases by 70%.

Also, since the thermal efficiency decreases by 14%, the fuel cost increases by about 16% as compared with a natural gas engine.

For this reason, both the initial cost and the running cost of an engine for biogas have been high cost.

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